Retinoid Metabolism Is Altered in Human and Mouse Cicatricial Alopecia Helen B. Everts, Kathleen A. Silva, Shalise Montgomery, Liye Suo, Monica Menser, Amy S. Valet, Lloyd E. King, David E. Ong, John P. Sundberg  Journal of Investigative Dermatology  Volume 133, Issue 2, Pages 325-333 (February 2013) DOI: 10.1038/jid.2012.393 Copyright © 2013 The Society for Investigative Dermatology, Inc Terms and Conditions

Figure 1 Immunoreactivity of dehydrogenase reductase (SDR family) member 9 (DHRS9) increased in C57BL/6J mice with mild dermatitis and biopsies from human patients with central centrifugal cicatricial alopecia (CCCA), but was reduced in mice with severe disease and biopsies from human patients with pseudopelade. Immunohistochemistry was performed with an antibody against DHRS9 in dorsal skin from chow fed C57BL/6J inbred mouse strain (B6) mice with no disease (a, n=18), mild disease (c, n=6), severe disease (e, n=38), biopsies from patients with no alopecia (b, normal Caucasian skin adjacent to pilar cyst removed by excision n=2, tinea capitus from African-American skin n=1), CCCA (d, n=14), or pseudopelade (f, n=3). b and f are from Caucasian patients, whereas d is from an African-American patient. Bar=101μM for main picture and 10.1μM for insets. Journal of Investigative Dermatology 2013 133, 325-333DOI: (10.1038/jid.2012.393) Copyright © 2013 The Society for Investigative Dermatology, Inc Terms and Conditions

Figure 2 Overview of retinoid metabolism and how these proteins changed during the progression of cicatricial alopecia. The left shows a schematic of RA synthesis, degradation, and signaling pathways in B6 mice. The right shows a summary of IHC results in chow fed B6 mice with no (control), mild, moderate, or severe disease. Immunoreactivity intensity ranges from dark to light; very strong (maroon), strong (red), moderate (hot pink), mild (pink), or undetectable (white). ALDH1A1, 2, and 3, retinal dehydrogenase 1, 2, and 3; B6, C57BL/6J inbred mouse strain; CL, companion layer; CRABP2, cellular retinoic acid-binding protein II; CRBP, cellular retinol-binding protein; CYP26A1, cytochrome P450 26 family member A1; DHRS9, dehydrogenase reductase (SDR family) member 9; IHC, immunohistochemistry; Mod., moderate; PM, premedulla; RA, retinoic acid; RARA and B, retinoic acid receptor alpha and beta. Journal of Investigative Dermatology 2013 133, 325-333DOI: (10.1038/jid.2012.393) Copyright © 2013 The Society for Investigative Dermatology, Inc Terms and Conditions

Figure 3 CRABP2 and retinoic acid receptor alpha (RARA) levels were increased in C57BL/6J mice with cicatricial alopecia. Immunohistochemistry was performed with antibodies against CRABP2 (a, c, e) and RARA (b, d, f), in mice with no disease (a, b), mild disease (c, d), or severe disease (e, f). Bar=101μM for main picture and 10.1μM for insets. Journal of Investigative Dermatology 2013 133, 325-333DOI: (10.1038/jid.2012.393) Copyright © 2013 The Society for Investigative Dermatology, Inc Terms and Conditions

Figure 4 Cicatrical alopecia was altered by dietary vitamin A and wax stripping. The percentage of mice with hair loss (a) was determined by visual inspection in B6 mice fed 4 (open bars), 28 (closed bars), or 56 (hatched bars) IU vitamin Ag−1 diet. H&E slides were then scored for % of hair follicles in anagen (b) and telogen (c), % of follicular dystrophy (d), % granulomas (e), and % of dermal scars (f). *Significant effect of wax stripping as analyzed by chi-square (P<0.05), #significant diet effect in the wax-stripped mice (P<0.05). Results with different letters are significantly different from each other in mice with hair loss (P<0.05). (c) r=-0.86, P<0.001. n=9–10 study 1, n=8–19 study 2. B6, C57BL/6J inbred mouse strain; H&E, hematoxylin and eosin; NA, not applicable. Journal of Investigative Dermatology 2013 133, 325-333DOI: (10.1038/jid.2012.393) Copyright © 2013 The Society for Investigative Dermatology, Inc Terms and Conditions

Figure 5 Dietary vitamin A altered liver and skin retinoids differently in the various studies. Liver retinol (a), liver retinyl palmitate (b), skin retinol (c), and skin retinyl esters (d) were analyzed by HPLC in study 1 (open bars, n=9–10), study 2 with no wax stripping (closed bars, n=8–19), and study 2 with wax stripping (hatched bars, n=10–16). *Significant study effect (P<0.001 in a, and P<0.05 in c), #significant effect of wax stripping (P<0.005), results with different letters are significantly different from each other (P<0.05). Journal of Investigative Dermatology 2013 133, 325-333DOI: (10.1038/jid.2012.393) Copyright © 2013 The Society for Investigative Dermatology, Inc Terms and Conditions